ruby-mustermann19 0.4.3+git20160621-1ubuntu1 (amd64 binary) in ubuntu bionic

 Mustermann19 is a library implementing patterns that behave like regular
 expressions for use in Ruby 1.9. Given a string pattern, Mustermann will turn
 it into an object that behaves like a regular expression and has comparable
 performance characteristics. Mustermann keeps its runtime dependencies to a
 minimum and is fully covered with specs and documentation.